I Love Linux Mint "Felicia." The install went aok and everything works, except the dvd playback. After poking around for a bit, I found that opening a DVD caused totem, mplayer, and vlc to disappear. After installing libdvdcss and updating medibunutu, I still had no playback until I installed ATI/AMD FGLRX proprietary driver for my ASUS mobo. Playback now worked except it had annoying flicker. Changing to X11 video output fixed the problem in the vlc preferences. In the mplayer changing preferences -> video -> available drivers to X11 (Ximage/Shm) did the trick. Finally, to get the totem working, I needed to change a line in ~/.config/totem/xine_config

#video driver to use#string, default autovideo.driver:xshm

I hope this info will spare anyone else from being stuck in the mud. Keep up the good work!